Illumination device, exposure apparatus, adjusting method, and method for manufacturing object

Abstract

An illumination device includes a plurality of light source units, each including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the illumination surface; and an illumination optical system that forms a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminates the illumination surface with the superposed light. In the light intensity distribution in the pupil plane of the illumination optical system, positions of shadows of all of the light blocking members included in one of the light source units are separated from positions of shadows of all of the light blocking members included in at least one of the remaining light source units.

What is claimed is: 
     
       1. An illumination device that illuminates an illumination surface, comprising:
 a plurality of light source units, each including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the illumination surface; and 
 an illumination optical system that forms a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminates the illumination surface with the superposed light, 
 wherein, in the light intensity distribution in the pupil plane of the illumination optical system, positions of shadows of all of the light blocking members included in one of the light source units are separated from positions of shadows of all of the light blocking members included in at least one of the remaining light source units. 
 
     
     
       2. The illumination device according to  claim 1 , wherein, in the light intensity distribution in the pupil plane of the illumination optical system, positions of shadows of all of the light blocking members included in all of the light source units are separated from each other. 
     
     
       3. The illumination device according to  claim 1 , wherein, when n is the number of shadows of the light blocking members of the light source units in the light intensity distribution in the pupil plane of the illumination optical system, each of n regions into which the pupil plane of the illumination optical system is divided such that the n regions each have a central angle of 360°/n has one of the shadows of the light blocking members disposed therein. 
     
     
       4. The illumination device according to  claim 1 , wherein, when n is the number of shadows of the light blocking members of the light source units in the light intensity distribution in the pupil plane of the illumination optical system, positions of the shadows of the light blocking members of the light source units are separated from each other by a central angle of 180°/n or more. 
     
     
       5. The illumination device according to  claim 1 , wherein, in the light intensity distribution in the pupil plane of the illumination optical system, the positions of the shadows of the light blocking members of the light source units are separated from each other by an equal central angle. 
     
     
       6. The illumination device according to  claim 1 , further comprising:
 an adjusting unit that adjusts an arrangement of the light blocking members of the light source units so that, in the light intensity distribution in the pupil plane of the illumination optical system, the positions of the shadows of the light blocking members are separated from each other. 
 
     
     
       7. The illumination device according to  claim 1 , wherein, in each of the light source units, the one or more light blocking members include a cable connected to an electrode of the light source. 
     
     
       8. The illumination device according to  claim 1 , wherein, in each of the light source units, the one or more light blocking members include a cooling nozzle for cooling an electrode of the light source. 
     
     
       9. The illumination device according to  claim 1 , wherein, in each of the light source units, the one or more light blocking members include a member in which a cable connected to an electrode of the light source and a cooling nozzle for cooling the electrode of the light source are integrated with each other. 
     
     
       10. The illumination device according to  claim 1 , wherein, in each of the light source units, the one or more light blocking members include, as separate components, a cable connected to an electrode of the light source and a cooling nozzle for cooling the electrode of the light source, and
 wherein, in the light intensity distribution in the pupil plane of the illumination optical system, a shadow of the cable included in one of the light source units overlaps a shadow of the cooling nozzle included in the one of the light source units. 
 
     
     
       11. The illumination device according to  claim 10 , wherein, in the light intensity distribution in the pupil plane of the illumination optical system, the shadow of the cable included in the one of the light source units and the shadow of the cooling nozzle included in the one of the light source units have the same width. 
     
     
       12. An exposure apparatus that transfers a pattern of a mask onto a substrate by exposure, the exposure apparatus comprising:
 the illumination device according to  claim 1  that illuminates the mask; and 
 a projection optical system that projects the pattern of the mask illuminated by the illumination device onto the substrate. 
 
     
     
       13. An illumination device that illuminates an illumination surface, comprising:
 a plurality of light source units, each including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the illumination surface; 
 an illumination optical system that forms a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminates the illumination surface with the superposed light; 
 a measurement unit that measures the light intensity distribution in the pupil plane of the illumination optical system; and 
 an adjusting unit that adjusts an arrangement of the light blocking members based on positions of shadows of the light blocking members in the light intensity distribution measured by the measurement unit. 
 
     
     
       14. The illumination device according to  claim 13 , wherein the adjusting unit adjusts the arrangement of the light blocking members so that, in the light intensity distribution in the pupil plane of the illumination optical system, positions of shadows of all of the light blocking members included in one of the light source units are separated from positions of shadows of all of the light blocking members included in at least one of the remaining light source units. 
     
     
       15. The illumination device according to  claim 13 , wherein the adjusting unit adjusts the arrangement of the light blocking members so as to reduce an intensity difference between two perpendicular directions in the light intensity distribution in the pupil plane of the illumination optical system. 
     
     
       16. An exposure apparatus that transfers a pattern of a mask onto a substrate by exposure, the exposure apparatus comprising:
 the illumination device according to  claim 13  that illuminates the mask; and 
 a projection optical system that projects the pattern of the mask illuminated by the illumination device onto the substrate. 
 
     
     
       17. An adjusting method for an illumination device including a plurality of light source units and an illumination optical system, each light source unit including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward an illumination surface, the illumination optical system forming a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminating the illumination surface with the superposed light, the adjusting method comprising the steps of:
 measuring the light intensity distribution in the pupil plane of the illumination optical system; and 
 adjusting an arrangement of the light blocking members based on positions of shadows of the light blocking members in the measured light intensity distribution. 
 
     
     
       18. An adjusting method for an exposure apparatus that transfers a pattern of a mask onto a substrate by exposure and that includes a plurality of light source units and an illumination optical system, each light source unit including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the mask, the illumination optical system forming a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminating the mask with the superposed light, the adjusting method comprising the step of:
 adjusting positions of shadows of the light blocking members in the light intensity distribution based on information of the pattern of the mask. 
 
     
     
       19. The adjusting method according to  claim 18 , further comprising the step of:
 acquiring information of a direction of the pattern of the mask, 
 wherein, in the adjusting step, the positions of shadows of the light blocking members are adjusted based on the acquired information of the direction of the pattern of the mask. 
 
     
     
       20. The adjusting method according to  claim 18 , wherein the pattern of the mask includes a plurality of periodic pattern elements having different periodic directions. 
     
     
       21. A method for manufacturing an object, comprising the steps of:
 performing an exposure process on a substrate by using an exposure apparatus that transfers a pattern of a mask onto the substrate by exposure and that includes an illumination device that illuminates the mask and a projection optical system that projects the pattern of the mask illuminated by the illumination device onto the substrate; 
 developing the substrate that has been subjected to the exposure process; and 
 manufacturing the object by processing the developed substrate, 
 wherein the illumination device includes
 a plurality of light source units, each including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the mask, and 
 an illumination optical system that forms a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminates the mask with the superposed light, and 
 
 wherein, in the light intensity distribution in the pupil plane of the illumination optical system, positions of shadows of all of the light blocking members included in one of the light source units are separated from positions of shadows of all of the light blocking members included in at least one of the remaining light source units. 
 
     
     
       22. A method for manufacturing an object, comprising the steps of:
 performing an exposure process on a substrate by using an exposure apparatus that transfers a pattern of a mask onto the substrate by exposure and that includes an illumination device that illuminates the mask and a projection optical system that projects the pattern of the mask illuminated by the illumination device onto the substrate; 
 developing the substrate that has been subjected to the exposure process; and 
 manufacturing the object by processing the developed substrate, 
 wherein the illumination device includes
 a plurality of light source units, each including a light source, a mirror that reflects light from the light source, and one or more light blocking members that block the light that is reflected by the mirror and travels toward the mask; 
 an illumination optical system that forms a light intensity distribution of superposed light, in which the light from each of the light source units is superposed, in a pupil plane and illuminates the mask with the superposed light; 
 a measurement unit that measures the light intensity distribution in the pupil plane of the illumination optical system; and 
 an adjusting unit that adjusts an arrangement of the light blocking members based on positions of shadows of the light blocking members in the light intensity distribution measured by the measurement unit.